In the sorting of fruit by weight, typically known as weight sizing, it is conventional to continuously convey a cup supporting each individual piece of fruit over a weighing scale or like mechanism so that the weight of the piece of fruit in each cup can be determined, and the cup can then be dropped at a future position depending upon the weight recorded. In more sophisticated systems, it is desirable to calculate the cumulative weight of all pieces of fruit deposited at a particular site to see that that cumulative weight exceeds a minimum weight but is within a specified tolerance. One example of that procedure is where it is desired to bag a quantity of fruit, such as a bag of apples, that is as little over the minimum weight (e.g. 3 pounds) as possible.
During weight sizing, it is of course desirable to convey the product as quickly as possible while ensuring accurate weighing of the individual pieces of fruit. Those two objectives are often mutually exclusive, however, and significant inaccuracies can occur. For instance utilizing the weight sizing apparatus such as shown in U.S. Pat. No. 4,262,807, typically the weight of each individual piece of fruit will read 5 percent lighter when that piece of fruit is weighed during active conveyance than the real weight of the fruit (i.e. weighed by the same weighing mechanism in a static condition). These inaccuracies relate to the inter-connections that are provided between the components of the sizing apparatus, and because of up and down movement of the fruit container with resulting frictional components that tend to distort the accuracy of the weight determination.
By utilizing a sizing apparatus in which the fruit cup containing the fruit is instantaneously transferred from a conveyance mode to a weighing mode (in operative association with the weighing mechanism), it is possible to significantly reduce the inaccuracies of the weighing in the active mode (as opposed to a static condition). For instance, a commercial weight sizer according to the structure and method illustrated in abandoned patent application Ser. No. 624,108 filed June 25, 1984, reads only about 3 percent lighter in an active conveyance mode than in the static weighing mode. However even a weight difference as little as 3 percent can be undesirable if consistent and accurate bagging is desired.
According to the present invention, a weight sizing apparatus and method are provided which are even more accurate than the procedures described above. According to the present invention, it is possible to weigh fruit, and like products, in an active conveyance mode with an accuracy of about 1 percent compared to the static mode. This is accomplished according to the present invention by cancelling out frictional up and down components that are typical of prior art procedures.
Not only is the apparatus according to the present invention more accurate, it is also easier to install and there is less wear on a number of the operative components thereof. Further, the apparatus according to the invention can be made so that the fruit cups are reversible so that not only do the cups last longer than prior art cups because of less wear, when operative components thereof are worn out the cup may merely be reversed, thus doubling its already extended life.
According to one aspect of the present invention an apparatus is provided for weight sizing of product, such as apples, tomatoes, or the like. The apparatus comprises the following elements: Product containing means for containing a product to be weighed by the weighing mechanism. Conveyance means for conveying the product containing means in a first direction. Track means connected to the weighing mechanism for supporting the product containing means during simultaneous weighing and conveyance. The product containing means, when containing a product, having a center of gravity, and the center of gravity being along a first line approximately bisecting the product containing means in the first direction. Support means associated with the product containing means for engaging the track means. The support means and the track means being provided in operative engagement with each other only on a first side of the first line; and connecting means for connecting the product containing means to the conveyance means so that when the support means engage the track means during weighing the product containing means is supported on a second side of the first line, opposite the first side, by the conveyance means although the conveyance means does not interfere with accurate weighing of product contained within the product containing means.
The track means comprises two distinct track segments connected to the weighing mechanism and extending parallel to each other and in the first direction, the track segments comprising first and second segments spaced from each other in the second direction; and the support means comprises first and second active support structures extending downwardly from the product containing means, both of the support structures being disposed on the first side of the line, while the support structures are disposed on opposite sides of a second line, the second line extending through the center of gravity in the second direction and substantially bisecting the product containing means. The first and second support structures are spaced from each other in the second direction so that only one of the support structures engages each of the track segments, and the first and second support structures are spaced from each other along the first direction a distance X. Each of the first and second track segments has a trailing edge thereof in the first direction, the trailing edges being spaced from each other a distance essentially equal to X.
Since track segments are not provided on both sides of the product containing means (fruit cup) there is no bouncing or jittering and therefore less inaccuracy. Also it is easier to align the track segments since they are right next to each other, and misalignments have a less significant affect on the operation of the apparatus.
According to another aspect of the invention, a fruit sizing cup assembly is provided. The assembly comprises the following components: A body for supporting a piece of fruit or the like, the body having a leading end, a trailing end, a top surface having formed therein a depression for receiving a piece of fruit, a bottom surface, and a pair of side surfaces, the side surfaces being generally parallel to each other. A yoke comprising an elongated main portion including means for attaching the yoke to a conveyance mechanism, and a pair of arms extending outwardly from the yoke on the same side thereof and generally parallel to each other. Means for pivotally mounting the body to the yoke arms so that the body may pivot with respect to the yoke arms about an axis extending generally perpendicular to the yoke arms and the body sides, and through the approximate center of gravity of the body; and means for limiting the pivotal movement of the body about the axis to a few degrees of pivotal rotation so that fruit conveyed by the body will not fall out merely by pivotal movement of the body with respect to the yoke about the axis.
A pair of active support structures also are provided extending downwardly from the bottom portion of the body, the active support structures being disposed on the same side of a first line extending through the center of gravity of the body generally parallel to the body sides, and the support structures being disposed on the opposite sides of the axis of rotation extending through the center of gravity generally parallel to the trailing and leading ends of the body. A pair of redundant support structures are disposed on the opposite side of the first line as the active support structures, and are substantially identical to the active support structures, so that after the active support structures wear down the body is reversible and the redundant support structures become active support structures.
According to yet another aspect of the present invention, an improved accuracy method of weighing product contained within a product container is provided. The method utilizes a weighing mechanism, and comprises the following steps: (a) Continuously conveying the product contained in the product container in a first direction by towing the product container with a tow rod which extends in a second direction, perpendicular to the first direction. (b) While continuously conveying the product in the product container, supporting the product container in a conveyance mode wherein it is not in operative association with the weighing mechanism. (c) At a given point in time during continuous conveyance of the product in the product container, conveying the product container in a weighing mode wherein it is in operative association with the weighing mechanism. (d) During conveyance in the weighing mode, supporting the product container on the weighing mechanism only on a first side of a line extending through the center of gravity of the product and product container in the first direction while providing for pivotal movement of the product container with respect to the tow rod about an axis parallel to the tow rod. (e) During conveyance in the weighing mode, supporting the product container on opposite sides of the axis of rotation; and, (f) instantaneously transferring the product container from the conveyance mode to the weighing mode.
It is the primary object of the present invention to provide an accurate, long life, and easily installed apparatus for weight sizing of fruit, or like products, and provide an associated method. This and other objects of the invention will become clear from an inspection of the detailed description of the invention, and from the appended claims.